The elements X, Y, Z and J have the indicated electron configurations starting with the innermost shell. The most metallic element is :
1. X = 2, 8, 3
2. Y = 2, 8, 8
3. Z = 2, 8, 8, 1
4. j = 2, 8, 8, 7
The correct sequence of increasing order of density is:
1. Li < K< Na < Rb < Cs
2. Li < Na < K < Rb < Cs
3. Cs < Rb < K < Na < Li
4. K < Li < Na < Rb < Cs
A common trend in both groups I and II elements in the periodic table, as the atomic number increases, is :
1. Oxidizing power increases
2. Atomic radius increases
3. Maximum valency increases
4. Reactivity with water decreases
The expected trend of change in atomic radius down the group is:
1. Continuous decrease
2. Continuous increase
3. Periodic one, an increase followed by a decrease
4. Periodic one, a decrease followed by an increase
The outer electronic configuration of Gd (Atomic no. 64) is:
1. 4f3 5d56d2
2. 4f8 5d106d2
3. 4f4 5d46d2
4. 4f7 5d16s2
The radius of La3+ (at. no. 57) is 1.06 The radius of Lu3+ (at.no. 71) might be:
1. 1.06
2. 0.85
3. 1.60
4. 1.40
Ionic radii are :
1. Inversely proportional to the effective nuclear charge.
2. Inversely proportional to the square of effective nuclear charge.
3. Directly proportional to the effective nuclear charge.
4. Directly proportional to the square of effective nuclear charge.
The correct arrangement of increasing order of atomic radius among Na, K, Mg and Rb is
1. Mg<K<Na<Rb
2. Mg<Na<K<Rb
3. Mg<Na<Rb<K
4. Na<K<Rb<Mg
Among the following species, the smallest ion is :
1. | Na+ | 2. | F- |
3. | O2- | 4. | N3- |
In scandium series, maximum distance between neutrons containing site and valence shell is of :-
1. Sc
2. Mn
3. Fe
4. Zn